1. Field of the Invention
The invention relates to a capture device for a bore hole of a fluid source.
2. Description of the Related Art
Petroleum and/or natural gas exist in a bubble in the ground in a petroleum and/or natural gas deposit. The bubble frequently is located below a cap rock that is gas- and/or fluid-tight, whereby a high pressure predominates in the bubble. To transport the petroleum and/or natural gas embedded in the bubble, it is known to install a bore into the cap rock via which an access to the bubble is established. To compensate for the high pressure in the bubble, a drilling fluid with a high density is filled into the bore hole during the drilling. The fluid column that thereby results generates a hydrostatic counter-pressure, whereby an uncontrolled escape of petroleum and/or natural gas from the bubble is suppressed. However, unwanted pressure increases in the bubble can occur in the drilling and in the later transport. If the deposit pressure is higher than the counter-pressure of the drilling fluid, petroleum and/or natural gas can penetrate into the bore hole, wherein the petroleum and/or the natural gas displaces the drilling fluid in the direction of the surface of the earth and ultimately itself reaches the surface as a blowout. In order to prevent (or at least dam) such a blowout, the bore hole must be sealed quickly. For this it is known to install a blowout preventer (bore seal) at the mouth of the bore hole. The blowout preventer is mounted at the bore and firmly anchored in the ground. The blowout preventer has a series of combined barrier devices that are mounted directly over the bore hole.
If the blowout preventer fails to stop the blowout of petroleum and/or natural gas, petroleum and/or natural gas arrives at the earth's surface without any control. The natural gas and/or petroleum that escapes from the bore hole is no longer available to be transported, whereby an economical loss occurs. However, it is more serious that a severe environmental pollution is incurred—primarily given the outflow of large quantities of petroleum and/or natural gas—that involves considerable ecological damage.
Bore holes have previously only been provided with the blowout preventer, wherein a disaster can occur upon its failure. In particular given bore holes in the deep sea, it is difficult to install the blowout preventer at significant depths and even more difficult to seal the bore hole again in the event of disaster. A redundant securing of the bore hole against the uncontrolled blowout of petroleum and/or natural gas in addition to the blowout preventer is not known.
It is an object of the invention to achieve a capture device for a bore hole of a fluid source, a method to secure the bore hole with the capture device and a use of the capture device to secure the bore hole, wherein the bore hole can be redundantly secured with the capture device in addition to a conventional device.